This thesis is an exploration of the politics of urban transformation in the immediate post-war period of British history, between 1945 and 1970. It centres on the Labour Party and considers the relationship of the party’s socialist aims to modernity as a stimulus for radical urban policy, particularly in terms of housing. Whilst prior historical accounts of post-war urban change have tended to eschew ideology as a serious catalyst for the reconstruction of British cities, arguing instead that pragmatism and corruption were of greater consequence, this thesis contends that a modern, socialist utopian ideal was a defining feature of urban transformation undertaken by Labour at both a local and national level. Archival material from Labour and the broader left of British politics, published sociological studies from the period 1945-70 and my own oral history interviews with key figures from the period lead this investigation. A thorough analysis of Labour’s approach to key aspects of the urban environment enables this thesis to challenge existing understandings of post-war urban transformation as irrational or hard-headed. The thesis examines the relationship of Labour to the housing market, urban planning, understandings of community and the party’s sense of history and modernity. It asserts that rent control, slum clearance and tower blocks were indicative of a modern, socialist urban vision for Labour, proposing that the ‘modern moment’ in twentiethcentury British history be taken into greater consideration. As urban history acquires greater prominence in an age of increasing urbanisation, engagement with the rationale behind past urban transformation can make a significant contribution to the understanding of why particular urban policies become reality.